2026 Physics Beyond Colliders and Non-Collider Physics Roadmap Workshop

2 Dec 2026, 08:30 → 4 Dec 2026, 18:50 Europe/Zurich

500/1-001 - Main Auditorium (CERN)

Gianluigi Arduini (CERN), Jamie Boyd (CERN), Markus Brugger (CERN), Joerg Jaeckel (Institut fuer theoretische Physik, Heidelberg University), Gunar Schnell, Urs Wiedemann (CERN), Johannes Bernhard (CERN)

The recent update to the European Strategy for Particle Physics has underscored the vital role of complementary approaches in advancing fundamental physics alongside the LHC and future colliders. In response, the CERN Directorate has launched a process to develop a 20-year roadmap for a Non-Collider Physics Programme (mandate), aiming to maximize the scientific potential of CERN’s accelerator complex and infrastructure for initiatives that complement the high-energy frontier.

The Physics Beyond Colliders (PBC) initiative, established in 2016, has already been fostering a vibrant community exploring innovative ideas. The workshop will review the progress of ongoing studies. It will also serve as a platform for gathering input to contribute to the shaping of the above roadmap and to further streamline the process for the analysis of new ideas and emerging opportunities for non-collider physics at CERN.

The event is open to all, but registration is required.

Deadline for registration: October 18, 2026.

Organising Committee:
Gianluigi Arduini, Johannes Bernhard, Jamie Boyd, Markus Brugger, Joerg Jaeckel, Gunar Schnell, Urs Wiedemann

Booking Form PBC Roadmap Workshop 2026.docx

Booking Form PBC Roadmap Workshop 2026.pdf

Non-Collider Physics Roadmap_Initiative_and_Study_Group_Mandate.pdf

Wednesday 2 December

08:30 → 10:00 Introduction

Convener: Jamie Boyd (CERN)

08:30 Address from the management

Speaker: Mark Thomson (CERN)

08:45 Overview of the PBC activities and results so far

Overview of the activities conducted under PBC from its inception: results and status

Speaker: Joerg Jaeckel (Institut fuer theoretische Physik, Heidelberg University)

09:05 Setting the stage: pressing questions that could be addressed by non-collider experiments

Pressing questions and how various experiments can address them

Speaker: Michelangelo Mangano (CERN)

09:40 Non-Collider Physics Roadmap

Introduction on the roadmap process and explain/discuss relevant timelines and underlying constraints: long-term schedule, long shout-downs and year end technical stops

Speaker: Markus Brugger (CERN)

10:00 → 10:30 Accelerator Complex

Convener: Jamie Boyd (CERN)

10:00 Injector capabilities and constraints/opportunities post-LS3

known limitations after LIU upgrades, possible mitigations and opportunities.
Specific AD/ELENA opportunities and possible upgrades will be covered in a later talk

Speaker: Foteini Asvesta (CERN)

10:30 → 11:00 Coffee Break and Group Photo

11:00 → 12:10 North and East Areas

Convener: Yacine Kadi (CERN)

11:00 Experiment & Test beams requirements (incl. long-term view)

Requirements from experiments with a view on Run4 and Run5
Limitations at CERN (seen from the user community), timeline (LS constraints), possibilities at CERN and elsewhere

Speakers: Paolo Martinengo (CERN), Johannes Bernhard (CERN)

11:35 Experimental Area capabilities and upgrade opportunities

Overview of the infrastructure and of the expected experiment requirements (including impact of MuonE, higher electron (EHN1) and muon (EHN2) intensities, hadrons for NA64, ...). Address CLOUD for East all and point to TECH session for MADMAX, RADES@North Area

Present consolidation plans and potential additional upgrades (e.g. vacuum upgrades M2, etc.)

Speaker: Dipanwita Banerjee (CERN)

12:10 → 13:30 Lunch

13:30 → 15:30 North Area

Convener: Gunar Schnell

13:30 NA60+/DICE Technical proposal and path to a TDR

The NA60+/DiCE experiment has been part of the PBC initiative since 2016. Its continuous support was a key factor on the path that eventually led to the recommendation of the experiment proposal in 2025 and to the RB approval in June 2026. In this presentation we will outline the physics program, the proposed set-up and the status of the R&D activities, meant to lead to the submission of a Technical Design Report in 2028. The current planning for the experiment data taking phase will also be discussed.

Speaker: Enrico Scomparin (INFN Torino (IT))

13:55 NA61/SHINE proposed proton and ion programme post LS3

Cover proton (including VLE) and ion (light + Pb) programme

Speakers: Eric Daniel Zimmerman (University of Colorado Boulder (US)), Seweryn Kowalski (University of Silesia (PL))

14:20 AMBER Phase II

Speaker: Prof. Bernhard Ketzer (University of Bonn (DE))

14:45 NA64 proposed programme post LS3

Cover electron, positrons, muons, hadron at North Area and hadrons at East Area

Speaker: Paolo Crivelli (ETH Zurich (CH))

15:10 MuonE: recent results and plans to go forward

The goal of the MUonE experiment at CERN is to measure the vacuum polarization contribution to the running of the fine-structure constant, α, in the t-channel for space-like momenta. This measurement aims to clarify the current picture concerning the muon anomalous magnetic moment and contribute to other precision measurements.

The method is based on a precision measurement of the differential angular distributions of elastic muon–electron scattering, obtained by colliding the high-intensity 160 GeV M2 muon beam at CERN with fixed light-material targets. Over the past few years, the project has progressed through increasingly complex stages. In the summer of 2025, a two-month pilot test run was successfully carried out using a reduced but fully functional version of the detector.

We are currently finalizing the analysis, with the aim of producing the first publication based on the 2025 test run. I will describe the present status of the MUonE experiment and its plans for the future.

Speaker: Umberto Marconi (Universita e INFN, Bologna (IT))

15:30 → 16:00 Coffee Break

16:00 → 16:40 North Area

Convener: Urs Wiedemann (CERN)

16:00 SHiP design status and construction/running scenarios

Speaker: Dr Anne-Marie Magnan (Imperial College (GB))

16:20 Neutrino Platform in Run 4

Speaker: Francesco Lanni (CERN)

16:40 → 18:00 AD/ELENA

Convener: Urs Wiedemann (CERN)

16:40 Mid-/Long-term experimental activities in AD/ELENA - Part-1

focus on fundamental symmetries, exotic physics, and gravity

Speaker: Prof. Stefan Ulmer (HHU Düsseldorf / RIKEN)

17:10 Mid-/Long-term experimental activities in AD/ELENA - Part-2

focus on nuclear physics

Speaker: Alexandre Obertelli

17:40 Possible AD/ELENA upgrades and consolidation requirements

Speaker: Davide Gamba (CERN)

18:00 → 19:00 SPSC

Convener: Urs Wiedemann (CERN)

18:00 SPSC perspective on future AD/ELENA and PS/SPS experiments and test beams

Physics opportunities at PS/SPS and AD/ELENA: what, why and how?

CERN’s injector complex offers a broad range of scientific opportunities beyond collider physics. This contribution will discuss the SPSC viewpoint on current and potential future programmes at PS/SPS and AD/ELENA, their scientific motivation, and their value for CERN and the wider particle physics community. Focusing on the areas reviewed by the SPS and PS Committee, it will discuss how these opportunities can be pursued within a coherent strategy, taking account of infrastructure needs, resources and realistic timescales.

Speaker: Sara Bolognesi (Université Paris-Saclay (FR))

18:30 Guided discussion

Speakers: Gunar Schnell, Urs Wiedemann (CERN)

19:00 → 20:30 Welcome Drink

Thursday 3 December

08:30 → 08:45 Introduction: HL-LHC

Convener: Massimiliano Ferro-Luzzi (CERN)

08:30 HL-LHC for physics beyond colliders

Short description of the LHC and its upgrade with emphasis on the implications for Physics Beyond Collider experiments

Speaker: Stefano Redaelli (CERN)

08:45 → 09:50 LHC-FT

Convener: Massimiliano Ferro-Luzzi (CERN)

08:45 The ALADDIN proposal (including infrastructure requirements)

ALADDIN and TWOCRYST talks back to back with 10 mins questions at the end.
Speakers should avoid overlap between the two talks

Speaker: Nicola Neri (Università degli Studi e INFN Milano (IT))

09:00 Results of the TWOCRYST machine studies

ALADDIN and TWOCRYST talks back to back with 10 mins questions at the end.
Speakers should avoid overlap between the two talks

Speaker: Chiara Maccani (Universita e INFN, Padova (IT))

09:25 SMOG2 results and LHCspin proposal

Speaker: Pasquale Di Nezza (INFN e Laboratori Nazionali di Frascati (IT))

09:50 → 10:20 Coffee Break

10:20 → 12:00 LHC LLP/Neutrinos

Convener: Joerg Jaeckel (Institut fuer theoretische Physik, Heidelberg University)

10:20 LLP/Neutrinos experimental proposals in the forward direction

Include brief overview of FASER and SND, their possible upgrades and FPF, SINE and UNDINE

Speaker: Alan Barr (University of Oxford (GB))

10:45 LLP experimental proposals at large angle

Overview of the existing proposals

Speaker: Matthew Daniel Citron (University of California Davis (US))

11:10 FIP/Neutrino Advisory Group's preliminary outcome

Speaker: Torben Ferber (KIT - Karlsruhe Institute of Technology (DE))

11:30 Open panel discussion on FIP/neutrino projects

FPF, FASER and SND upgrades, ANUBIS, CODEX-b, MATHUSLA, SHIFT, SINE, UNDINE ...

Speakers: Joerg Jaeckel (Institut fuer theoretische Physik, Heidelberg University), Joerg Jaeckel (ITP Heidelberg)

12:00 → 13:30 Lunch

13:30 → 14:15 AICE

Convener: Clara Murgui Galvez (CERN)

13:30 AICE proposal and recent updates

AICE proposal and its technical implementation in two talks back to back with 10 mins questions at the end
Speakers should avoid overlap

Speaker: Oliver Buchmuller (Imperial College (GB))

13:55 Technical infrastructure for AICE and possible implementation

AICE proposal and its technical implementation in two talks back to back with 10 mins questions at the end
Speakers should avoid overlap

Speaker: Sergio Calatroni (CERN)

14:15 → 15:15 LHCC

Convener: Clara Murgui Galvez (CERN)

14:15 LHCC perspective on existing proposals

Speaker: Prof. Alfons Weber (JGU Mainz & Fermilab)

14:45 Guided discussion on LHC-based experiments

Moderated by the conveners of the 3 sessions related to LHC

Speakers: Clara Murgui Galvez (CERN), Joerg Jaeckel (Institut fuer theoretische Physik, Heidelberg University), Joerg Jaeckel (ITP Heidelberg), Massimiliano Ferro-Luzzi (CERN)

15:15 → 15:45 Coffee Break

15:45 → 18:20 n_TOF/n_ACT/ISOLDE

Convener: Hanne Heylen (CERN)

15:45 ISOLDE perspectives

Speaker: Prof. Luis M Fraile (CERN)

16:10 ISOLDE Infrastructure (status and possibilities, necessities)

Speakers: Erwin Siesling (CERN), Joachim Vollaire (CERN)

16:35 n_TOF perspectives

Speakers: Nikolaos Patronis (K. U. Leuven, Instituut voor Kern- en Stralingsfysica, Celestijnenlaan 200D, B-3001 Leuven), Prof. Nikolaos Patronis (University of Ioannina (GR))

17:00 n_TOF/n_ACT Infrastructure (status and possibilities, necessities)

Speakers: Dr Marco Calviani (CERN), Oliver Aberle (CERN)

17:25 INTC perspective on future experiments at ISOLDE/n_TOF

Requirements, possible timeline, international landscape
What can/should be done at CERN and what can be done elsewhere.

Speaker: Silvia Leoni (Università degli Studi e INFN Milano (IT))

17:50 Guided discussion on n_TOF/ISOLDE opportunities

Speaker: Hanne Heylen (CERN)

18:20 → 19:00 Roadmap

Convener: Markus Brugger (CERN)

18:20 Future Process for New Ideas and Proposals (Discussion)

A coherent process for handling new non-collider physics ideas, proposals and enabling technologies will be important to provide clarity to present and future user communities and to ensure their early integration into CERN’s scientific and technical planning. First considerations foresees a single point of entry, connecting emerging ideas and formal proposals with the required studies and CERN support, while making systematic use of the established scientific and technical committees and ensuring consistency with the long-term Non-Collider Physics Roadmap.

The discussion will seek feedback on how such a process could operate in practice, including the appropriate level and timing of decisions, regular follow-up of evolving proposals, boundary conditions to be established upfront, and the scientific and technical support required at different stages. Particular attention will be given to maintaining sufficient operational flexibility and to finding the appropriate balance between supporting promising ideas, enabling them through infrastructure and capabilities, and driving developments in line with the laboratory’s longer-term strategy.

Speaker: Markus Brugger (CERN)

19:00 → 21:00 Reception

Friday 4 December

08:30 → 10:15 TECH

Convener: Babette Dobrich (Max Planck Society (DE))

08:30 Axion searches with non accelerator experiments

Axion Physics Beyond Colliders:

Axions are the prime example of Nambu–Goldstone bosons associated with symmetry breaking at energy scales far beyond the direct reach of particle colliders. Their extremely weak interactions motivate a rich and rapidly evolving experimental landscape.

Three basic approaches are being pursued: laboratory experiments, helioscopes searching for axions from the Sun, and haloscopes searching for axion dark matter. These experiments directly probe weakly coupled particles associated with the dark sector, complementing collider searches that often exploit observable portal interactions between new particles and the Standard Model.

Using selected axion searches as examples, the opportunities and challenges of this diverse experimental program will be discussed.

Speaker: Axel Lindner (Deutsches Elektronen-Synchrotron (DE))

08:55 Updates on the Quantum Technology Initiative and other opportunities related to CERN technology infrastructure

• QTI-specific technology developments that is relevant and could be of interest to non-collider physics;
• the expertise QTI contributes and could contribute to non-collider physics, and how this fits with the relevant timescales, for example those envisaged in the Phase-III proposal;
• complementarity and potential synergies between QTI, PBC and the non-collider physics roadmap.

Speaker: Sofia Vallecorsa (CERN)

09:20 Non-Collider Physics opportunities and related Technology at national laboratories

Present outcome of the LDG Taskforce

Speaker: Dr Philipp Schmidt-Wellenburg

09:45 Guided discussion on non-accelerator experiments

Speaker: Babette Dobrich (Max Planck Society (DE))

10:15 → 10:45 Coffee Break

10:45 → 12:00 Future Opportunities

Convener: Markus Brugger (CERN)

10:45 The NuScope proposal

Nu Scope proposal (physics and experiment description) and beamline design back to back with 10 mins discussion at the end
Speakers should avoid overlap

Speakers: Francesco Terranova (Universita & INFN, Milano-Bicocca (IT)), Mathieu Perrin-Terrin (Aix Marseille Univ, CNRS/IN2P3, CPPM, Marseille, France)

11:05 NuScope beamline: preliminary design

Preliminary design of the beamline and preliminary location in the accelerator/experimental area complex, outline of the required studies

Nu Scope proposal (physics and experiment description) and beamline design back to back with 10 mins discussion at the end
Speakers should avoid overlap

Speaker: Matteo Capitani (CERN/University of Ioannina (GR))

11:30 Design of a gamma factory proof of principle experiment at the SPS

The contribution will present the current design of the Gamma Factory proof-of-principle experiment at the CERN SPS, aimed at demonstrating hard X-ray production and laser cooling of relativistic partially stripped ions. The experiment combines a high-power Fabry-Perot enhancement cavity, synchronized laser-ion interactions and dedicated SPS beam optics, with simulations predicting measurable reductions in both longitudinal momentum spread and transverse emittance, together with high-flux hard X-ray production. The current engineering status, outstanding feasibility questions and CERN infrastructure requirements will be reviewed, together with the key technical demonstrations and indicative timescale required for the SPS PoP to provide a meaningful decision point towards future Gamma Factory experiments at the LHC.

Speaker: Eduardo Granados (CERN)

12:00 → 13:30 Lunch

13:30 → 14:50 Future Opportunities

Convener: Johannes Bernhard (CERN)

13:30 FCCee injector complex and experimental areas infrastructure

Overview of the main parameters of the FCC-ee injectors (up to the Booster) and possible experimental area infrastructure for beyond colliders physics

Speaker: Dr Simone Gilardoni (CERN)

13:55 FCCee injector physics opportunities

A condensed and partly digested summary of the preceding workshop

Speaker: Ivo Schulthess (ETH Zurich)

14:20 Guided discussion on future opportunities

Speakers: Johannes Bernhard (CERN), Markus Brugger (CERN)

14:50 → 15:20 Coffee Break

15:20 → 16:45 Roadmap

Convener: Urs Wiedemann (CERN)

15:20 Identified present/future synergies in terms of physics opertunities, operation, and infrastructure opportunities

Speaker: Johannes Bernhard (CERN)

15:45 Roadmap - preliminary analysis and overview (including future PBC-like portal)

Speaker: Markus Brugger (CERN)

16:15 Guided discussion on overall roadmap

16:45 → 17:00 Close-out